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Description
Based on the 850{mu}m dust continuum data from SCUBA-2 at James Clerk Maxwell Telescope (JCMT), we compare overall properties of Planck Galactic Cold Clumps (PGCCs) in the {lambda} Orionis cloud to those of PGCCs in the Orion A and B clouds. The Orion A and B clouds are well-known active star-forming regions, while the {lambda} Orionis cloud has a different environment as a consequence of the interaction with a prominent OB association and a giant HII region. PGCCs in the {lambda} Orionis cloud have higher dust temperatures (T_d_=16.13+/-0.15K) and lower values of dust emissivity spectral index ({beta}=1.65+/-0.02) than PGCCs in the Orion A (T_d_=13.79+/-0.21K, {beta}=2.07+/-0.03) and Orion B (T_d_=13.82+/-0.19K, {beta}=1.96+/-0.02) clouds. We find 119 substructures within the 40 detected PGCCs and identify them as cores. Out of a total of 119 cores, 15 cores are discovered in the {lambda} Orionis cloud, while 74 and 30 cores are found in the Orion A and B clouds, respectively. The cores in the {lambda} Orionis cloud show much lower mean values of size R=0.08pc, column density N(H_2_)=(9.5+/-1.2)x10^22^cm^-2^, number density n(H_2_)=(2.9+/-0.4)x10^5^cm^-3^, and mass M_core_=1.0+/-0.3M_{sun}_ compared to the cores in the Orion A [R=0.11pc, N(H_2_)=(2.3+/-0.3)x10^23^cm^-2^, n(H_2_)=(3.8+/-0.5)x10^5^cm^-3^, and M_core_=2.4+/-0.3M_{sun}_] and Orion B [R=0.16pc, N(H_2_)=(3.8+/-0.4)x10^23^cm^-2^, n(H_2_)=(15.6+/-1.8)x10^5^cm^-3^, and M_core_=2.7+/-0.3M_{sun}_] clouds. These core properties in the {lambda} Orionis cloud can be attributed to the photodissociation and external heating by the nearby H II region, which may prevent the PGCCs from forming gravitationally bound structures and eventually disperse them. These results support the idea of negative stellar feedback on core formation.
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